CVE-2026-75957 Ultimate Multisite WordPress - Authentication Bypass

Ultimate Multisite WordPress plugin <= 2.15.0 contains an authentication bypass caused by improper validation in the checkout_form parameter in login_customer_after_checkout, letting unauthenticated attackers log in as any user by knowing their email, exploit requires targeted user to have no pre-existing Ultimate Multisite customer record.

CVSS base score 9.8 /10
Critical
CISA KEV
Not listed
Public exploit
None known
Authentication
Not required
EPSS
0.58% chance of exploitation in 30 days
View the NVD record ↗

Details

Type
Authentication Bypass
Impact
Broken Authentication
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
1 October 2026
Updated
15 October 2026
Weakness
CWE-287

Vendor fix

Update to a version later than 2.15.0 or the latest available version.

Patching closes this CVE. It does not tell you which of your systems run the affected version, or what else is exposed alongside them.

References

← All CVEs